A kind of energy-conserving hydraulic cylinder of thrust auto-changing
Technical field
The utility model belongs to oil hydraulic cylinder technical field.Be specifically related to a kind of energy-conserving hydraulic cylinder of thrust auto-changing.
Background technique
At present, in hydraulic equipment, the thrust of oil hydraulic cylinder is one of important process performance of hydraulic system, for the thrust of regulator solution cylinder pressure, existing method is to come a grade hole of living or exposing different oil extractions with the movement of pressure controlled valve control valve body, change the size of valve port or the switching of change valve port, reach the object that regulates thrust.But these pressure controlled valves are generally contained on the working connection of hydraulic system, other oil circuit or oil circuit, which position no matter composition multi-stage pressure regulating system, be contained in, and hydraulic oil all has the pressure loss by pressure controlled valve, this loss will be converted into heat energy, and hydraulic fluid temperature is raise.The too high hydraulic oil that can cause of oil temperature is rotten, reduces the operating life of hydraulic oil, wastes energy and increases cost of production, and multi-stage pressure regulating operation is simultaneously controlled inconvenient, poor stability.
The pressure loss producing in order to reduce pressure controlled valve, adopts variable displacement pump fuel feeding at present.But variable displacement pump complex structure, involves great expense, and rate of fault is high, and maintenance difficulty is large, whole hydraulic equipment price improved.
Summary of the invention
The utility model is intended to overcome above-mentioned technological deficiency, and object is to provide and a kind ofly converts simple, energy saving, reduces costs, convenient operating maintenance, conversion process good stability and can improve the energy-conserving hydraulic cylinder of the thrust auto-changing of hydraulic system efficiency.
To achieve these goals, the technical solution adopted in the utility model is: described oil hydraulic cylinder comprises large end cap, guide sleeve, cylinder body, large piston, large piston rod, small piston, small piston rod, small end cover and repid cut-off valve.
Cylinder body is the entirety of large cylinder body and little cylinder body composition.Large end cap is fixedly equipped with in the end of large cylinder body, and small end cover is fixedly equipped with in the end of little cylinder body, and guide sleeve is close to large end cap and is fixed on concentrically in large cylinder body.Large cylinder body has the first hydraulic fluid port, and the first hydraulic fluid port is near guide sleeve; Little cylinder body has the second hydraulic fluid port, and the second hydraulic fluid port is near small end cover.The joint of large inboard wall of cylinder block and little inboard wall of cylinder block has 4 triangular grooves symmetrically.
Large piston is arranged in large cylinder body, and a side of large piston is fixed with large piston rod concentrically, and guide sleeve and large end cap are stretched out in the end of large piston rod.The opposite side of large piston has small piston hole concentrically, and the aperture in small piston hole equates with the external diameter of small piston, and the degree of depth in small piston hole equates with the thickness of small piston; Large piston and large piston rod have small piston rod through hole concentrically, and the internal diameter of small piston rod through hole and small piston rod external diameter equate.Have valve seat orifice with the large piston side of small piston hole homonymy, the hole wall of valve seat orifice has the first annular oil groove and the second annular oil groove from inside to outside successively, the first annular oil groove communicates with large piston rod rod chamber by the first oil duct, the second annular oil groove communicates with the small piston hole of large piston by the second oil duct, and repid cut-off valve is fixed in valve seat orifice.
Small piston rod is fixedly connected with small piston is concentricity, and small piston is arranged in little cylinder body, and the gap of small piston and little cylinder body is 15 ~ 35 μ m.Small piston rod passes small piston rod through hole, with on the small piston ring surface of small piston rod homonymy, have concentrically annular seal groove, the radius of annular seal groove is greater than the distance of the large piston center line of the second oil duct hydraulic fluid port distance and is less than the radius in the small piston hole of large piston, and annular seal groove is equipped with the first seal ring.
Repid cut-off valve is made up of valve pocket, spring, spool, fixed cover and the second seal ring; Spring packs in spool, and the opening end of spool packs valve pocket inwardly into.Valve pocket is cylindric, and the barrel of valve pocket has the 3rd hydraulic fluid port, and the 3rd hydraulic fluid port communicates with the first annular oil groove; The inwall of valve pocket has the 3rd annular oil groove, and the 3rd annular oil groove communicates with the second annular oil groove by the 4th hydraulic fluid port, and the close open end of valve pocket outer wall is equipped with the second seal ring.Spool is also cylindric, and the barrel of spool has the 5th hydraulic fluid port, and the 5th hydraulic fluid port communicates with the 3rd annular oil groove, the closed end of spool is provided with push rod, centered by fixed cover, be provided with the discoid of through hole, fixed cover is fixedly connected with large piston by screw, and the push rod of spool is arranged in the through hole of fixed cover.
The hole wall of large end cap is equipped with dust ring, the hole wall of guide sleeve is equipped with the 3rd seal ring, and the 4th seal ring is equipped with in the cylndrical surface of large piston, and support ring is equipped with in the both sides of the 4th seal ring, the cylndrical surface of small piston evenly has 5 ~ 7 balancing slits, and the 5th seal ring is equipped with at the middle part of small piston rod.
The axial length H of described triangular groove is 6 ~ 8mm, and the radial length L of triangular groove is 4 ~ 6mm; Triangular groove is isosceles triangle in the projection of horizontal plane and vertical guide, and triangular groove is 45 ~ 75 ° at the isosceles angle of horizontal plane projection, and described vertical guide is the face vertical with the radial direction of triangular groove.
The groove width of described balancing slit is 0.5 ~ 0.8mm, and groove depth is 0.6 ~ 1.0mm.
The material of described large piston, large piston rod, small piston and small piston rod is cast steel, the equal chromium plating in surface of large piston, large piston rod, small piston and small piston rod, and chromium coating thickness is 0.01 ~ 0.02mm.
Working procedure of the present utility model:
In the time that hydraulic oil enters large piston rod rod chamber from the first hydraulic fluid port, large piston inwardly moves to the bottom of large cylinder body, the push rod of spool is under the reaction of large cylinder base, spool Compress Spring, the hydraulic oil of large piston rod rod chamber is entered in repid cut-off valve by the first oil duct, the 5th hydraulic fluid port of spool and the second oil duct are connected, and hydraulic oil flows to the rod chamber of small piston, and small piston rod is inwardly retracted.Otherwise, when hydraulic oil enters rodless cavity from the second hydraulic fluid port, small piston rod is protruding, and the hydraulic oil of small piston rod chamber enters large piston rod rod chamber by repid cut-off valve, in the time that small piston outwards moves to the bottom, small piston hole of large piston, the first seal ring seals the second oil duct, large piston is also outwards motion under hydraulic oil effect, and in the time that the push rod of spool leaves the bottom of large cylinder body, spool is under the effect of spring, cut off the second oil duct, realize heavy load externally acting at a slow speed.
Owing to adopting technique scheme, the utility model compared with prior art has following good effect:
1, the utility model adopts double-piston double piston-rod structure, and small piston rod is protruding through large piston and large piston rod, realizes quick low carrying moving, and now large piston and large piston rod are motionless.In the time that small piston touches the bottom in small piston hole of large piston, small piston and large piston synchronous motion, with heavy load microinching.The conversion of speed and thrust must HYDRAULIC CONTROL SYSTEM, and self is completed by described oil hydraulic cylinder.
Small piston rod carries out relative movement through small piston rod through hole, and in the time of the pressure of hydraulic oil and constant flow, small piston and small piston rod can be realized little load rapid movement; When small piston arrives behind bottom, small piston hole, under pressure oil effect, large piston and large piston rod are realized heavy load microinching.Thrust and rate conversion process are to realize by repid cut-off valve.
2, the utility model adopts repid cut-off valve, can be completed by spring and push rod realizing and cut off or connect between small piston rod chamber and large piston rod chamber, cutting off or connect, and conversion is simple.
3, the utility model adopts the integral structure of large cylinder body and repid cut-off valve, and composition one composite component, has simplified structure and the control of hydraulic system, makes oil hydraulic cylinder multifunction.
4, the utility model adopts clearance seal and seal ring to seal the form combining, on longer junction plane, adopt the 5th seal ring sealing, between the cylndrical surface of small piston and the inwall of little cylinder body, adopt clearance seal, not only reduce the surface friction drag of oil hydraulic cylinder, can reduce again small piston rod surface and piston and the greatly machining accuracy of piston rod inwall greatly, reduce cost.
5, the utility model is having 4 triangular grooves symmetrically with the joint of large inboard wall of cylinder block and little inboard wall of cylinder block, and the hydraulic shock producing while undergoing mutation because of the volume of cavity volume in order to slow down has improved the stability of conversion process.
Therefore, the utlity model has that conversion is simple, energy saving, reduce costs, convenient operating maintenance, the feature of hydraulic system efficiency and conversion process good stability of improving.
Brief description of the drawings
Fig. 1 is a kind of structure diagram of the present utility model;
Fig. 2 is the enlarged diagram of Fig. 1 repid cut-off valve 19.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is further described, not the restriction to its protection domain:
embodiment 1
A kind of energy-conserving hydraulic cylinder of thrust auto-changing.As shown in Figure 1, described oil hydraulic cylinder comprises large end cap 2, guide sleeve 4, cylinder body 24, large piston 6, large piston rod 25, small piston 11, small piston rod 26, small end cover 14 and repid cut-off valve 19.
As shown in Figure 1, cylinder body 24 is the entirety that large cylinder body 5 and little cylinder body 13 form.Large end cap 2 is fixedly equipped with in the end of large cylinder body 5, and small end cover 14 is fixedly equipped with in the end of little cylinder body 13, and guide sleeve 4 is close to large end cap 2 and is fixed on concentrically in large cylinder body 5.Large cylinder body 5 has the first hydraulic fluid port 22, the first hydraulic fluid ports 22 near guide sleeve 4; Little cylinder body 13 has the second hydraulic fluid port 15, the second hydraulic fluid ports 15 near small end cover 14.The joint of large cylinder body 5 inwalls and little cylinder body 13 inwalls has 4 triangular grooves 9 symmetrically.
As shown in Figure 1, large piston 6 is arranged in large cylinder body 5, and a side of large piston 6 is fixed with large piston rod 25 concentrically, and guide sleeve 4 and large end cap 2 are stretched out in the end of large piston rod 25.The opposite side of large piston 6 has small piston hole concentrically, and the aperture in small piston hole equates with the external diameter of small piston 11, and the degree of depth in small piston hole equates with the thickness of small piston 11; Large piston 6 and large piston rod 25 have small piston rod through hole concentrically, and the internal diameter of small piston rod through hole and small piston rod 26 external diameters equate.As depicted in figs. 1 and 2, have valve seat orifice with large piston 6 sides of small piston hole homonymy, the hole wall of valve seat orifice has the first annular oil groove 28 and the second annular oil groove 35 from inside to outside successively, the first annular oil groove 28 communicates with large piston rod rod chamber 23 by the first oil duct 20, the second annular oil groove 35 communicates with the small piston hole of large piston 6 by the second oil duct 18, and repid cut-off valve 19 is fixed in valve seat orifice.
As shown in Figure 1, small piston rod 26 is fixedly connected with small piston 11 is concentricity, and small piston 11 is arranged in little cylinder body 13, and small piston 11 is 15 ~ 35 μ m with the gap of little cylinder body 13.Small piston rod 26 passes small piston rod through hole, with on small piston 11 ring surfaces of small piston rod 26 homonymies, have concentrically annular seal groove, the radius of annular seal groove is greater than the distance of large piston 6 center lines of the second oil duct 18 hydraulic fluid ports distance and is less than the radius in the small piston hole of large piston 6, annular seal groove is equipped with the first seal ring 10, to prevent that the hydraulic oil of rodless cavity 16 from entering the second oil duct 18.
As shown in Figure 2, repid cut-off valve 19 is made up of valve pocket 29, spring 27, spool 36, fixed cover 33 and the second seal ring 32; Spring 27 packs in spool 36, and the opening end of spool 36 packs valve pocket 29 inwardly into.Valve pocket 29 is cylindric, and the barrel of valve pocket 29 has the 3rd hydraulic fluid port 37, the three hydraulic fluid ports 37 and communicates with the first annular oil groove 28; The inwall of valve pocket 29 has the 3rd annular oil groove 34, the three annular oil grooves 34 and communicates with the second annular oil groove 35 by the 4th hydraulic fluid port 30, and the close open end of valve pocket 29 outer walls is equipped with the second seal ring 32.Spool 36 is also cylindric, the barrel of spool 36 has the 5th hydraulic fluid port 31, the 5th hydraulic fluid port 31 communicates with the 3rd annular oil groove 34, the closed end of spool 36 is provided with push rod, centered by fixed cover 33, be provided with the discoid of through hole, fixed cover 33 is fixedly connected with large piston 6 by screw, and the push rod of spool 36 is arranged in the through hole of fixed cover 33.
As shown in Figure 1, the hole wall of large end cap 2 is equipped with dust ring 1, the hole wall of guide sleeve 4 is equipped with the 3rd seal ring 3, the 4th seal ring 8 is equipped with in the cylndrical surface of large piston 6, support ring 7 is equipped with in the both sides of the 4th seal ring 8, the cylndrical surface of small piston 11 evenly has 5 ~ 7 balancing slits 12, and the 5th seal ring 21 is equipped with at the middle part of small piston rod 26.
As shown in Figure 1, the axial length H of described triangular groove 9 is 6 ~ 7mm, and the radial length L of triangular groove 9 is 4 ~ 5mm; Triangular groove 9 is isosceles triangle in the projection of horizontal plane and vertical guide, and triangular groove 9 is 45 ~ 60 ° at the isosceles angle of horizontal plane projection, and described vertical guide is the face vertical with the radial direction of triangular groove 9.
The groove width of described balancing slit 12 is 0.5 ~ 0.7mm, and groove depth is 0.6 ~ 0.8mm.
The material of described large piston 6, large piston rod 25, small piston 11 and small piston rod 26 is cast steel, the equal chromium plating in surface of large piston 6, large piston rod 25, small piston 11 and small piston rod 26, and chromium coating thickness is 0.01 ~ 0.02mm.
embodiment 2
A kind of energy-conserving hydraulic cylinder of thrust auto-changing.The present embodiment is except following technical parameter, and all the other are with embodiment 1:
The axial length H of described triangular groove 9 is 7 ~ 8mm, and the radial length L of triangular groove 9 is 5 ~ 6mm; Triangular groove 9 is isosceles triangle in the projection of horizontal plane and vertical guide, and triangular groove 9 is 60 ~ 75 ° at the isosceles angle of horizontal plane projection, and described vertical guide is the face vertical with the radial direction of triangular groove 9.
The groove width of described balancing slit 12 is 0.6 ~ 0.8mm, and groove depth is 0.8 ~ 1.0mm.
The working procedure of this embodiment:
In the time that hydraulic oil enters large piston rod rod chamber 23 from the first hydraulic fluid port 22, large piston 6 inwardly moves to the bottom of large cylinder body 5, the push rod of spool 36 is under the reaction of large cylinder body 5 bottoms, spool 36 Compress Springs 27, the hydraulic oil of large piston rod rod chamber 23 is entered in repid cut-off valve 19 by the first oil duct 20, the 5th hydraulic fluid port 31 and second oil duct 18 of spool 36 are connected, and hydraulic oil flows to the rod chamber 17 of small piston, and small piston rod 26 is inwardly retracted.Otherwise, when hydraulic oil enters rodless cavity 16 from the second hydraulic fluid port 15, small piston rod 26 is protruding, the hydraulic oil of small piston rod chamber 17 enters large piston rod rod chamber 23 by repid cut-off valve 19, in the time that small piston 11 outwards moves to the bottom, small piston hole of large piston 6, the first seal ring 10 seals the second oil duct 18, large piston 6 is also outwards motion under hydraulic oil effect, in the time that the push rod of spool 36 leaves the bottom of large cylinder body, spool 36 is under the effect of spring 27, cut off the second oil duct 18, realize heavy load externally acting at a slow speed.
Owing to adopting technique scheme, this embodiment compared with prior art has following good effect:
1, this embodiment adopts double-piston double piston-rod structure, and small piston rod 26 is protruding through large piston 6 and large piston rod 25, realizes quick low carrying moving, and now large piston 6 and large piston rod 25 are motionless.In the time that small piston 11 touches the bottom in small piston hole of large piston 6, small piston 11 and large piston 6 are synchronized with the movement, with heavy load microinching.Speed and load change must HYDRAULIC CONTROL SYSTEM, and self completed by described oil hydraulic cylinder.
Small piston rod 26 carries out relative movement through small piston rod through hole center, and in the time of the pressure of hydraulic oil and constant flow, small piston 11 and small piston rod 26 can be realized little load rapid movement; When small piston 11 arrives behind bottom, small piston hole, under pressure oil effect, large piston 6 and large piston rod 25 are realized heavy load microinching.Load and rate conversion process are to realize by repid cut-off valve 19.
2, this embodiment adopts repid cut-off valve 19, can be completed by spring 27 and push rod realizing and cut off or connect between small piston rod chamber 17 and large piston rod chamber 23, cutting off or connect, and conversion is simple.
3, this embodiment adopts the integral structure of large cylinder body 5 and repid cut-off valve 19, and composition one composite component, has simplified structure and the control of hydraulic system, makes oil hydraulic cylinder multifunction.
4, this embodiment adopts clearance seal and seal ring to seal the form combining, on longer junction plane, adopt the 5th seal ring 21 to seal, between the cylndrical surface of small piston 11 and the inwall of little cylinder body 13, adopt clearance seal, not only reduce the surface friction drag of oil hydraulic cylinder, can reduce again small piston rod 26 surfaces and piston 6 and the greatly machining accuracy of piston rod 25 inwalls greatly, reduce cost.
5, this embodiment is having 4 triangular grooves 9 symmetrically with the joint of large cylinder body 5 inwalls and little cylinder body 13 inwalls, and the hydraulic shock producing while undergoing mutation because of the volume of cavity volume in order to slow down has improved the stability of conversion process.
Therefore, this embodiment have that conversion is simple, energy saving, reduce costs, convenient operating maintenance, the feature of hydraulic system efficiency and conversion process good stability of improving.